Squeaky Brakes

[bfi2906]

I've read the threads here and in the main forum. but there doesn't seem to be a conclusive answer.

Has anyone found a reliable way of getting rid of the brake squeak under light pedal pressure.

I have the slotted factory rotors. I thought I'd read somewhere on here that the "slots" prevent glazing. Anyone able to comment on this???

Interestingly, when I asked the dealer to fix it, they offered to chamfer the pads, and deglaze the rotors - for a mere $130 (car's still under warranty) - I declined. When I asked what they did to deglaze the rotors, I was told it was "like a lite remachining". I've always been told that BMW doesn't recomment remachining its rotors at all. Maybe the slotted rotors are different.

[dtcoff]

Slotted (and drilled) rotors don't really stop glazing, rather they allow the gases created under hard braking to disappate from between the rotor and pad surfaces. Kind of like the tread on tyres allow water to escape and let the tyre grip the road. Normal road usage doesn't generate enough heat to require slotting, but it looks cooler and gives the marketing people something to crow about and charge more.

Glazing is the buildup of brake pad material on the rotor. This is especially bad if changing brake pad materials. Deglazing a rotor usually means just skimming with a oribital sander to remove any pad buildup and get back to raw steel.

To stop squeaking, try a little copper grease on the backing plate of the pad.

[bfi2906]

Originally Posted by dtcoff

Slotted (and drilled) rotors don't really stop glazing, rather they allow the gases created under hard braking to disappate from between the rotor and pad surfaces. Kind of like the tread on tyres allow water to escape and let the tyre grip the road. Normal road usage doesn't generate enough heat to require slotting, but it looks cooler and gives the marketing people something to crow about and charge more.

Glazing is the buildup of brake pad material on the rotor. This is especially bad if changing brake pad materials. Deglazing a rotor usually means just skimming with a oribital sander to remove any pad buildup and get back to raw steel.

To stop squeaking, try a little copper grease on the backing plate of the pad.

Thanks for that - makes it much clearer.

What does the copper grease do - capture the dust and thus keep the it off the rotors?

[dtcoff]

The squeaking noise generally comes from the pads against the calipers, not neccessarily between pad and rotor (road pads). Copper grease provides a small amount of lubrication and works in high temperature applications.

[AussieRacer]

I tried numerous fixes. Only cure that worked for me was new pads. I went with Endless Concept Ewig from Race Brakes in Yarraville VIC. Perfect fitment for 135i. Not cheap, but same braking performance as OEM, better heat stability, no dust and no squeaking. I'm sure other pad option exist, I just took the trusted advice from Race Brakes as they have never been wrong before for me.

[bfi2906]

A good wash seems to have largely solved the problem. While that's good, I guess it means it'll come back when the dust builds up again.

I'll give the grease a go, and see what happens.

Thanks guys

[Orlin]

I just had Westside BMW replace my brake pads for me for $140. I supplied the front and rear pads and sensors and now the squeak is gone! total price for all the parts delivered to my door was 311.53 GBP. I got everything from www.bmminiparts.com, they were very helpful and the shipping took less then a week. If anyone wants any info such as the person I was dealing with or part numbers etc just send me a pm and ill be more then happy to help.